Reverse-time migration using multidirectional wavefield decomposition method
Xue Hao1,3 and Liu Yang1,2,3
1. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing 102249, China.
2. Faculty of Petroleum, Karamay Campus of China University of Petroleum (Beijing), Xinjiang 834000, China.
3. CNPC Key Laboratory of Geophysical Prospecting, China University of Petroleum (Beijing), Beijing 102249, China.
Abstract Reverse-time migration has attracted more and more attention owing to the advantages of high imaging accuracy, no dip restriction, and adaptation to complex velocity models. Cross-correlation imaging method is typically used in conventional reverse-time migration that produces images with strong low-frequency noise. Wavefield decomposition imaging can suppress such noise; however, some residual noise persists in the imaging results. We propose a 2D multidirectional wavefield decomposition method based on the traditional wavefield decomposition method. First, source wavefields and receiver wavefields are separated into eight subwavefields, respectively. Second, cross-correlation imaging is applied to selected subwavefields to produce subimages. Finally, the subimages are stacked to generate the final image. Numerical examples suggest that the proposed method can eliminate the low-frequency noise effectively and produce high-quality imaging profiles.
This work was supported by National Natural Science Foundation of China (No. 41474110) and the Scientific Research Starting Foundation of China University of Petroleum-Beijing at Karamay (No. RCYJ2018A-01-001).
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